Contemporary wireless telephones, commonly known as cell phones, incorporate many new features such as digital cameras. However, the quality of pictures taken using such “camera phones” is compromised by constraints on cost, weight and size driven by consumers' preferences for smaller and lighter devices. Manufacturers can increase picture quality by using higher quality camera components, such as higher quality lenses or detector arrays. However, a manufacturer must either raise the price of its product to cover the higher cost of the higher quality components, or reduce the number of other features to offset increased costs and maintain current pricing, in either case placing the manufacturer at a competitive disadvantage.
Furthermore, regardless of the quality of the picture-taking components included in a camera phone, such components may degrade with time, reducing picture quality. For instance, a camera phone captures images using a detector array such as a charged coupled device (CCD) or a complementary metal-oxide semiconductor (CMOS) device. A detector element —equivalent to a pixel—may fail or degrade with repeated use, resulting in a dead spot in the captured image data and hence in the rendered image. The user is faced with either accepting lower quality images or purchasing a new camera phone.
A dead or degraded detector element may also be detected as a result of quality checks made during the manufacturing process. Typically, if a detector array includes too many failed or degraded detector elements, it is discarded by the manufacturer. Discarding components that fail quality checks, in particular components that just barely fail to pass, can increase manufacturing costs and hence the price of the product.